Dual mode absorbent tampon

ABSTRACT

A dual mode absorbent tampon comprising a mass of absorbent material compressed into a generally cylindrical shape, in a first mode of the tampon. The mass of absorbent material comprising a homogeneous mixture of a plurality of fibers which comprise at least a first type of fiber and a second type of fiber, where the first type of fiber is bondable to fibers of the plurality of fibers. At least a portion of the first type of fibers are bonded in a pre-determined pattern to adjacent fibers of the plurality of fibers wherein absorption by the tampon causes at least a portion of the mass of absorbent material to expand into a non-cylindrical shape which is dependent upon the pre-determined pattern, in a second mode of the tampon.

This application claims priority as a continuation application of U.S.application Ser. No. 11/117,899, filed on Apr. 29, 2005. The entirety ofapplication Ser. No. 11/117,899 is incorporated herein by reference,

BACKGROUND

The present invention concerns personal hygiene products, moreparticularly, catamenial tampons. Currently, there are two basic typesof catamenial tampons used for feminine hygiene. The first type is adigital tampon which is designed to be inserted into a woman's vaginadirectly by the user's fingers. The second type is a tampon which isdesigned to be inserted with the aid of an applicator. Both types areusually made by folding or rolling a loosely associated strip ofabsorbent material into an elongated shape often referred to as a“softwind.” The softwind is then radially and/or biaxially compressedinto a pledget. The pledget may or may not include a cover. In bothtypes of tampons, a withdrawal string is attached to the absorbent,either before or after compression, to facilitate removal of the tamponfrom the users vagina after it has absorbed a certain quantity of bodyfluid, such as menses, blood, etc.

It has been found that many tampons, both digital as well as thosedelivered by an applicator, are often unable to prevent prematureleakage of body fluid. Premature leakage can result from a number offactors. For example, one factor is that the tampon does not properlyfit above the introital region of the vagina. Another example is thatthe tampon is not shaped correctly to intercept fluid flow through thevaginal canal. Still another example is that the folds and convolutionsof the vagina are not all in contact with the tampon and therefore bodyfluid is able to bypass the tampon.

While various types of tampons exist in the art, there remains a needfor a tampon product that helps better prevent leakage of body fluidsoon after being inserted into a woman's vagina and provides utilizationof the absorbent during use. The applicants have surprisingly inventedsuch a tampon, as discussed further herein.

SUMMARY

Various definitions used throughout the specification and claims areprovided first, followed by a description of various aspects of theinvention.

DEFINITIONS

As used herein forms of the words “comprise”, “have”, and “include” arelegally equivalent and open-ended. Therefore, additional non-recitedelements, functions, steps or limitations may be present in addition tothe recited elements, functions, steps, or limitations.

As used herein, “disposable” means being disposed of after a single useand not intended to be washed and reused.

As used herein, the term “autogenous bonding”, “autogenously bondable”and similar forms of these words, means bonding provided by fusionand/or self-adhesion of fibers and/or filaments without an appliedexternal adhesive or bonding agent. Autogenous bonding can be providedby contact between fibers and/or filaments while at least a portion ofthe fibers and/or filaments are semi-molten or tacky. Autogenous bondingmay also be provided by blending a tackifying resin with thethermoplastic polymers used to form the fibers and/or filaments. Fibersand/or filaments formed from such a blend can be adapted to self-bondwith or without the application of pressure and/or heat. Solvents mayalso be used to cause fusion of fibers and filaments which remain afterthe solvent is removed.

As used herein, the term “non-cylindrical shape” means a tampon having asecond zone of the tampon where the cross-sectional Diameter of thesecond zone is at least 5% greater than a cross-sectional Diameter of atleast a first zone of the tampon, such Diameter of the respective zonesbeing determined according to the Radial Expansion Test herein. Examplesnot drawn to scale, and rather, slightly exaggerated for illustrationpurposes, are seen in FIGS. 2, 4 and 6. The at least 5% greater value isbelieved to readily distinguish the inventive tampons from prior tamponsthat through manufacturing variability may have had zones with varyingDiameters (i.e., none of the prior tampons had first and second zoneswith Diameters that differed by more than 5%, as well as none of theprior packages of multiple tampons consistently having each tampon inthe pack which would have a non-cylindrical shape when the tamponabsorbed liquid).

As used herein, the term “cross-section”, “cross-sectional” and similarforms of these words, mean the plane which extends laterally through thetampon and which is orthogonal to the longitudinal axis of the tampon.

As used herein, the term “Diameter” and similar forms of this word,means the cross-sectional diameter (22 and 26 are examples) of thetampon as measured according to the Radial Expansion Test herein.

As used herein the term “polymer” generally includes, but is not limitedto, homopolymers, copolymers, such as, for example, block, graft, randomand alternating copolymers, terpolymers, etc. and blends andmodifications thereof. Furthermore, unless otherwise specificallylimited, the term “polymer” shall include all possible geometricalconfigurations of the material. These configurations include, but arenot limited to, isotactic, syndiotactic and random symmetries.

In response to one or more of the discussed difficulties or problemsencountered in the art, a new tampon has been invented that starts outgenerally cylindrical in shape in a first mode and then becomesnon-cylindrical in shape in a second mode to help prevent leakage ofbody fluid soon after being inserted into a woman's vagina, and whichcan also, advantageously, provide good utilization of the entireabsorbent during use. The purposes and features of the present inventionwill be set forth in and are apparent from the description that follows,as well as will be learned by practice of the invention. Additionalfeatures of the invention will be realized and attained by the productand process particularly pointed out in the written description andclaims hereof, as well as from the appended drawings.

In one aspect, the invention provides a dual mode absorbent tampon. Thetampon includes a mass of absorbent material compressed into a generallycylindrical shape, in a first mode of the tampon. The mass of absorbentmaterial includes a homogeneous mixture of a plurality of fibers whichcomprise at least a first type of fiber and a second type of fiber,where the first type of fiber is bondable to fibers of the plurality offibers. At least a portion of the first type of fibers are bonded in apre-determined pattern to adjacent fibers of the plurality of fiberswherein absorption of liquid by the tampon causes at least a portion ofthe mass of absorbent material to expand into a non-cylindrical shapewhich is dependent upon the pre-determined pattern, in a second mode ofthe tampon.

In another aspect, the invention provides a dual mode absorbent tampon.The tampon includes a mass of absorbent material compressed into agenerally cylindrical shaped, in a first mode of the tampon. The mass ofabsorbent material includes a plurality of fibers which include a firsttype of fiber and a second type of fiber, the second type of fiberhaving a material composition different than the first type of fiber. Atleast a portion of the first type of fibers are bonded in apre-determined pattern to adjacent fibers of the plurality of fiberswherein absorption of liquid by the tampon causes at least a portion ofthe mass of absorbent material to expand into a non-cylindrical shapewhich is dependent upon the pre-determined pattern, in a second mode ofthe tampon.

In yet other aspects, the invention provides various configurations andoptional features for, the plurality of fibers, the shape of the tampon,and Radial Expansion, and such features, in various combinations, notavailable in existing tampons.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and are intended toprovide further explanation of the invention claimed. The accompanyingdrawings, which are incorporated in and constitute part of thisspecification, are included to illustrate and provide a furtherunderstanding of the disposable absorbent tampons of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings are merely representative and are not intended to limit thescope of the claims. Like parts depicted in the drawings are referred toby the same reference numerals.

FIG. 1 is a dual mode absorbent tampon of the invention, in the firstmode of the tampon.

FIG. 2 is the tampon of FIG. 1, in the second mode of the tampon.

FIG. 3 is an alternate dual mode absorbent tampon of the invention, inthe first mode of the tampon.

FIG. 4 is the tampon of FIG. 3, in the second mode of the tampon.

FIG. 5 is another alternate dual mode absorbent tampon of the invention,in the first mode of the tampon.

FIG. 6 is the tampon of FIG. 5, in the second mode of the tampon.

DETAILED DESCRIPTION

Referring to the Figures, a variety of forms of dual mode tampon 10 areshown which can be useful for absorbing body fluid from a woman'svagina, especially during her menstrual cycle. The tampon 10 is designedto be inserted above the introital region of a woman's vagina and isdesigned to function so as to intercept the fluid flow of menses, blood,and other body fluids and prevent the fluid from exiting the vagina. Thetampon 10 includes a mass of absorbent material 12 compressed into agenerally cylindrical shape, in a first mode of the tampon (e.g., FIGS.1, 3 and 5). The generally cylindrical shape may have a variety ofcross-sectional shapes spanning from a circular cross-sectionconfiguration to more of an oval cross-section configuration to more ofa square cross-sectional configuration to more of a rectangularcross-sectional configuration. Tampon 10 generally has an insertion end14 and a trailing end 16. The insertion end 14 is designed to be thefirst part of the tampon which enters the woman's vaginal cavity. Itshould be noted that, while in use, the tampon 10 will be entirelypositioned within the woman's vagina.

The mass of absorbent material can be formed from absorbent fibers whichare assembled into an absorbent sheet or ribbon. One exemplary type ofsheet for practicing the invention is described in patent applicationPCT/EP2004/006441 titled: “Airlaid Process With Improved Throughput”,filed Jun. 16, 2003, published Dec. 29, 2004 as WO2004/113608, which isowned by the same assignee as this application and is incorporatedherein by reference. Alternatively, the material 12 can be formed from ageneral mass of absorbent fibers. In either case, the fibers are thenrolled or assembled, respectively, and compressed into a generallycylindrical and elongated shape. Two processes for forming such anabsorbent sheet are known as “carding” and “airlaying.” Depending uponthe desired absorbency one desires in the finished tampon, the basisweight of the absorbent sheet can vary. The U.S. Food and DrugAdministration (FDA) has set absorbency standards for “junior”,“regular”, “super”, “super-plus” and “super-plus-plus” size tampons. Inorder to meet the certain standards for these sizes, the absorbentsheets are targeted to have basis weights of about 100 grams per squaremeter (gsm), 120-150 gsm, 170-180 gsm, 210-230 gsm, and 240-260 gsm,respectively, and as much as 270-290 gsm. Typically, the formationprocess is controlled to produce an absorbent sheet with a width ofbetween about 40 mm to about 60 mm, preferably about 50 mm. The basisweight and/or the length of the tampon 10 can also be adjusted to formthe different size tampons.

Material 12 is a plurality of fibers which include at least a first typeof fiber and a second type of fiber. The first type of fiber (alsoreferred to generally herein as binder fiber) is bondable to fibers ofthe plurality of fibers. Additionally, the plurality of fibers may be ahomogeneous mixture of the types of fibers and additionally, oralternatively, the second type of fiber may have a material compositiondifferent than the first type of fiber. For example, the bondable firsttype of fibers may be polymer fibers. Material 12 includes a second typeof fiber which may be cellulosic fibers such as wood pulp, cotton,rayon, viscose, LYOCELL® which is from Lenzing Company of Austria, ormixtures of these or other cellulosic fibers. The second type fiber maybe a natural type fiber and/or it may not be autogenously bondable toother like type fibers. The absorbent material can be a blend of viscoseand binder fibers. Some blends which are believed to work well include ablend of about 70% viscose to about 95% viscose with the remainder about30% binder fiber to about 5% binder fiber; and more advantageously about85-90% viscose and the remainder about 15-10% binder fiber. Theparticular blend of fibers can vary depending upon one's preference incombination with also achieving the features of the invention.

More specifically, for example, the plurality of fibers could be eithersynthetic fibers or natural fibers, as long as they have the desiredabsorbent and/or bondable characteristics. Synthetic fibers includethose made from polyolefins, polyamides, polyesters, rayon, acrylics,viscose, superabsorbents, LYOCELL® regenerated cellulose and any othersuitable synthetic fibers known to those skilled in the art. Manypolyolefins are available for fiber production, for examplepolyethylenes such as Dow Chemical's ASPUN® 6811A linear low densitypolyethylene, 2553 LLDPE and 25355 and 12350 high density polyethyleneare such suitable polymers. The polyethylenes have melt flow rates,respectively, of about 26, 40, 25 and 12. Fiber forming polypropylenesinclude Exxon Chemical Company's ESCORENE® PD 3445 polypropylene andMontell Chemical Co.'s PF304. Another fiber could be a bi-componentpolyester sheath and polyethylene core and known as T255 made by Treviraof Germany. Other polyolefins are also available. Suitable rayon fibersare 1.5 denier Merge 18453 fibers from Acordis Cellulose FibersIncorporated of Axis, Ala. The fibers can be treated by conventionalcompositions and/or processes to enable or enhance wettability.

Natural fibers can include wool, cotton, flax, hemp and wood pulp. Woodpulps include standard softwood fluffing grade such as CR-1654 (USAlliance Pulp Mills, Coosa, Ala.). Pulp may be modified in order toenhance the inherent characteristics of the fibers and theirprocessability. Crimping may be imparted to the fibers, e.g., byconventional means. Curl may be imparted to the fibers, e.g., by methodsincluding chemical treatment or mechanical twisting. Curl is typicallyimparted before crosslinking or stiffening. Pulps may be stiffened bythe use of crosslinking agents such as formaldehyde or its derivatives,glutaraldehyde, epichlorohydrin, methylated compounds such as urea orurea derivatives, dialdehydes such as maleic anhydride, non-methylatedurea derivatives, citric acid or other polycarboxylic acids. Some ofthese agents are less preferable than others due to environmental andhealth concerns. Pulp may also be stiffened by the use of heat orcaustic treatments such as mercerization. Examples of these types offibers include NHB416 which is a chemically crosslinked southernsoftwood pulp fibers which enhances wet modulus, available from theWeyerhaeuser Corporation of Tacoma, Wash. Other useful pulps aredebonded pulp (NF405) and non-debonded pulp (NB416) also fromWeyerhaeuser. HPZ3 from Buckeye Technologies, Inc of Memphis, Tenn., hasa chemical treatment that sets in a curl and twist, in addition toimparting added dry and wet stiffness and resilience to the fiber.Another suitable pulp is Buckeye HP2 pulp and still another is IPSupersoft from International Paper Corporation.

For the cellulosic fiber (e.g., viscose, rayon, etc.), the fibers shouldhave a staple length of between about 5 mm to about 35 mm. The fibersshould have a denier of between about 2 to about 6. Denier is a unit offineness of yarn based on a standard of 50 milligrams (mg) for 450meters of yarn. The fibers can have a circular, a bi-lobal, a tri-lobalcross-sectional configuration, or some other cross-sectionalconfiguration known to those skilled in the art. The bi-lobalconfiguration has a cross-sectional profile which looks like a dog bonewhile the tri-lobal configuration has a cross-sectional profile whichlooks like a “Y”. The fibers can also be bleached if desired.

When cotton fibers are used, the cotton fibers should have a staplelength of between about 5 millimeters (mm) to about 20 mm. The cottonfibers should generally have a fiber size of between about 150 micronsto about 280 microns. The cotton fibers can also be bleached if desired.Bleaching will make the cotton fibers whiter in appearance.

The plurality of at least two types of fibers includes a sufficientquantity of the first type of bondable fibers so that when at least aportion of the first type of fibers are bonded in a pre-determinedpattern to adjacent fibers of the plurality of fibers, then absorptionof liquid by the tampon causes at least a portion of the mass ofabsorbent material to expand into a non-cylindrical shape 18 which isdependent upon the pre-determined pattern, in a second mode of thetampon (e.g., FIGS. 2, 4 and 6). Although it should be clear, it is bythis selective expansion capability that the tampon can provide betterand/or more uniform, leakage protection across a broader range of thefemale population. Said another way, through the pre-determined patterna portion of the tampon can expand as needed to better fit and the sealthe vaginal canal during use of the tampon. The selective expansion ofthe portion of the tampon into the non-cylindrical shapes 18 occursbecause of normal absorbent material expansion characteristics of themass of absorbent material, as opposed to use of any resilient member(e.g., see U.S. Pat. Nos. 5,755,906 and 6,039,716, both of assigneeKimberly-Clark Worldwide, Inc., or the like). Rather, the normalabsorbent material expansion characteristics of a portion of thecylindrically shaped mass of absorbent material are retarded by bonding(partially to completely, depending on desired total absorptioncharacteristics for the tampon) the first type of fibers in that portionof the tampon (i.e., consistent with the desired pre-determined pattern)to adjacent fibers of the plurality of fibers.

The pre-determined pattern can be achieved in a variety of ways. Forexample, an adhesive or bonding agent may be applied to, or incorporatedinto, the tampon to selectively prevent a portion of the tampon fromexpanding into the non-cylindrical shape to the same degree that anotherportion does expand when the tampon absorbs liquid. Such adhesive orbonding agent may be applied with the fibers during formation of themass of absorbent material and then activated to cause bonding betweenthe types of fibers, e.g., activation by heat, radiation and/orpressure.

Advantageously, and additionally or alternatively, the first type offibers may be autogenously bondable with the first, second, and anyother type of fibers in the mass of absorbent material. The inventorshave surprisingly found that autogenous bonding can be particularlyadvantageous because it also simplifies manufacturing of tampons.Without being limited to a theory of understanding, one unexpected andnot before possible advantage comes from being able to use a singleforming material (i.e., one that includes at least two types of fiberswith at least one type of fiber being autogenously bondable, and whichmay be homogeneous or not so homogeneous if a sufficient quantity of theautogenously bondable fibers are located near the outer surface of theto be formed tampon), as opposed to using two separate materials to makeselect portions of the tampon so that in use a different andnon-cylindrical shape expansion pattern can be obtained by the differentrates of expansion of the two different materials. Another unexpectedand not before possible advantage comes from being able to use a singleforming material (i.e., as just noted previously), and avoid using aconventional cover material over the tampon, because the tampon of theinvention with the a sufficient quantity of the autogenously bondablefibers located near the outer surface of the to be formed tampon can bebonded to act like a cover.

For example, for autogenous bonding, such first type of fiber could bethermally bonded to the other fibers, or bonded by other forms ofradiation (e.g., microwave, ultrasonics, etc.). With regard to thermalbonding, one skilled in the art will appreciate that the temperature towhich the materials, or at least the bond sites thereof, are heated forheat bonding will depend not only on the temperature of the equipment orother heat sources but on the resident time of the materials on theheated surfaces, the compositions of the materials, the basis weights ofthe materials, their specific heats and thermal conductivities, and, thedesired bond strengths in relationship to the pre-determined pattern tobe imparted upon the mass of absorbent material and thus resultingexpansion into the non-cylindrical shape when absorbing body fluids.Typically, the bonding can be conducted at a temperature of from about80° C. to about 130° C. Advantageously, the bonding can be conducted ata temperature of from about 90° C. to about 125° C. More advantageously,the bonding can be conducted at a temperature of from about 110° C. toabout 120° C. The typical pressure range, on the tampon, can be fromabout 200 to about 800 kPa (kiloPascals). The preferred pressure range,on the tampon, can be from about 300 to about 600 kPa. However, for agiven combination of materials, and in view of the herein containeddisclosure, the processing conditions necessary to achieve satisfactorybonding can be readily determined by one of skill in the art.

The bondable fibers, e.g., polymer fibers, can have some tackiness toenhance bonding and autogenous bonding. For example, the polymer itselfcan be tacky when formed into fibers or, optionally, a compatibletackifying resin can be added to the extrudable polymer compositionsdescribed above to provide tackified fibers and/or fibers thatautogenously bond. In regard to the tackifying resins and tackifiedextrudable polymer compositions, note the resins and compositions asdisclosed in U.S. Pat. No. 4,787,699, to Moulin. Any tackifier resin canbe used which is compatible with the polymer and can withstand the highprocessing (e.g., extrusion) temperatures. If the polymer is blendedwith processing aids such as, for example, polyolefins or extendingoils, the tackifier resin should also be compatible with thoseprocessing aids. Generally, hydrogenated hydrocarbon resins areavailable tackifying resins, because of their better temperaturestability. REGALREZ™ and ARKON™ series tackifiers are examples ofhydrogenated hydrocarbon resins. ZONATAK™ 501 Lite is an example of aterpene hydrocarbon. REGALREZ™ hydrocarbon resins are available fromHercules incorporated. ARKON™ series resins are available from ArakawaChemical (U.S.A.) Inc. The present invention is not limited to use ofthese tackifying resins, and other tackifying resins which arecompatible with the other components of the composition and canwithstand the high processing temperatures, can also be used.

The non-cylindrical shape 18 of the tampon when in the second mode maybe mushroom shaped (FIG. 6), bottle shaped (FIG. 4), cone shaped (FIG.2), or any other desired shape whereby one portion maintains more of theoriginal generally cylindrical shape (even if with an expandedcross-section due to expansion with fluid absorption) and anotherportion expands into an expanded non-cylindrical shape to better assistin sealing the vaginal cavity and absorbing liquid during use. Becauseit may not be apparent, the shapes depicted in the drawings are not toscale and only generally represent the varying proportionalrelationships between portions of the tampon 10. Also, the drawings ofthe tampons (FIGS. 2, 4 and 6) into their expanded shapes representmaximum possible expansions into the depicted non-cylindrical shapes. Itshould be understood that the tampon would seek to attain this shapeinside the vagina in use but that it would be a “soft” expansion withpossible irregularities in the non-cylindrical shape in order toaccommodate a woman's unique body geometry for fit and comfort whilebeing an absorbent tampon.

Yet further considerations for the non-cylindrical shapes include thenon-cylindrical shape being referred to as a first zone 20 and anadjacent second zone 24 (see FIG. 6). The first zone may have a firstDiameter 22 corresponding to the generally cylindrical shape and thesecond zone may have a second Diameter 26 corresponding to thenon-cylindrical shape 18 and the second Diameter may be greater than thefirst Diameter. Further in this regard, and though not required, thesecond Diameter may be, in degrees of increasing advantage: at least 10%greater, at least 15% greater, at least 20% greater, at least 25%greater and up to 40% greater, than the first Diameter. In this way, thedesired sealing features of the tampon 10 may be better implemented, asdesired.

The tampon 10 further includes a withdrawal string 38 for assisting inremoving the tampon 10 from the woman's vagina. The withdrawal string 38is attached to the absorbent material 12, and preferably, to the firstand second ends, 14 and 16 respectively, of the material 12. One methodof attaching the withdrawal string 38 is to form an aperture or holethrough the absorbent sheet or ribbon. The withdrawal string 38 is thenthreaded through the aperture and looped upon itself so as to cinch itsecure to the absorbent 12. The free ends of the withdrawal string 38are then tied in a knot 40 to assure that the withdrawal string 38 willnot separate from the material 12. The knot 40 also serves to preventfraying of the withdrawal string 38 and to provide a place or pointwhere a woman can grasp the withdrawal string 38 when she is ready toremove the tampon 10 from her vagina. It should be noted that thewithdrawal string 38 holds the first and second ends, 14 and 16respectively, in direct contact with one another and may, but need not,limit the amount they can expand while positioned within the woman'svagina. It should be noted that the withdrawal string 38 can be securedto and/or attached to various areas of the tampon 10 and can passthrough the absorbent 12. The withdrawal string 38 can also be attachedeither before the mass of absorbent material 12 is compressed or afterit is formed into the tampon.

The withdrawal string 38 can be constructed from various types ofthreads or ribbons. A thread or ribbon may be made from 100 percentcotton fibers and/or other materials in whole or part. The string may bebonded to the material 12, with or without tying (e.g., using one ormore of the ways as for making the pre-determined pattern in material12) to material 12 before or as material 12 is being formed into thegenerally cylindrical shape. In this way, there is no need (or lessneed) for tying the string to the tampon and better assurance that thestring will stay in place and attached to the tampon before, during useand during withdrawal of the tampon till it is ready for disposal.Advantageously (though not required because the bonding characteristicsof the first type of fibers in the material 12 can be sufficient), andas with the material 12, the string 38 may include bondable material,e.g., the same type of material compositions as for the material 12 orthose with similar bonding characteristics. As such, the string may be aplurality of string fibers including at least a first type of stringfiber being bondable to adjacent fibers and where the string isautogenous bonded with the mass of absorbent material.

The withdrawal string 38 should have a length which extends beyond theend of the tampon 10 from between about 2 inches to about 8 inches(about 51 mm to about 203 mm), preferably from about 4 inches to about 6inches (about 102 mm to 152 mm), and most preferably, about 5 inches(about 127 mm). The withdrawal string 38 can be dyed and/or treated withan anti-wicking agent, such as wax, before being secured to the material12. The anti-wicking agent will facilitate and prevent body fluids fromwicking along the withdrawal string 38 and contacting the inner surfaceof a woman's undergarment. A dry, clean withdrawal string 38 ispreferred by the user, especially when she goes to remove the tampon 10from her vagina.

Tampon 10 may, advantageously, additionally include autogenous bondslocated around the surface of the tampon which help impart a smoothappearance to the tampon after removal from packaging and prior to useof the tampon. In this way, the tampon can avoid use of a cover which istraditionally used to impart smoothness and/or better maintain the shapeof the tampon prior to and during use.

Example

The following material, for example, is suitable to provide features fortampons of the invention. An airlaid material was produced on a Danweb®Airlaid line containing 93% trilobal rayon fiber (3.3 dtex, 5 mm length)and 7% binder fiber (PET/PE, 3.0 dtex, 6 mm length), with a density of0.04 g/cc and a basis weight of 180 gsm. This material was cut intorolls of 50 mm width and converted as tampon ribbon on a conventionalRuggli® tampon machine type CL.2/CL 3 into radially wound tampons with awithdrawal string. The tampon was treated with ultrasonic waves using aBranson 8500® machine and a circular sonotrode, at a pressure of 300 kPaand a dwell time of 0.3 sec, in the center section of the tampon (e.g.,to impart a pre-determined pattern like FIGS. 3 and 4).

Test Methods

The testing set forth herein is performed where the tampons to be testedare conditioned 24 hours and tested under TAPPI standard conditions of23±1° C. and 50±2% RH. The test equipment discussed is exemplary andshould be used to conduct the testing, however, alternative equipmentthat is equivalent in all material respects for the given test can beused also (but in the event of conflict between test results the testresults from the exemplary equipment shall control).

Radial Expansion Test

After conditioning 10 sample tampons per above, each is treated asfollows. Weigh 1000 mL (replenish as needed to be able to saturate alltampons tested) of commercially available saline solution (sodiumchloride), 0.9+/−0.005% (w/w) aqueous isotonic saline and pour into awide mouth beaker capable of holding at least 1500 mL. Drop the sampleinto the solution and allow to remain there for at least 60 seconds (andno more than 10 minutes) in order to reach saturation capacity(carefully push sample under the surface of the solution if necessary tohelp begin absorption). Delicately remove the sample being careful tonot compress the sample any more than needed to get it to the diametermeasuring equipment per the Diameter Measurement Procedure hereafter (inthis regard, it is recommended that the visibly smallest diameterportion of the sample be carefully grasped to remove the sample from thesolution and get it to the diameter measuring equipment). After removingthe sample, hold above the solution beaker for about 2 minutes to allowunabsorbed solution to drip back into the beaker. After the 2 minutes,proceed immediately to the diameter measuring equipment and determinethe diameter of the sample using the Diameter Measurement Procedure. Tensamples are tested in this manner and the diameter of each zone for eachsample is added together and the collective total diameter for that zonedivided by 10, which thereby determines the Diameter, of the respectivefirst or second zone, of the tampon which is discussed herein and setforth in the claims.

Diameter Measurement Procedure

The diameter of an absorbent tampon of the invention is found using theCompression Tester model KES-FB-2 manufactured by Kato Tech Co., Ltd inJapan. The diameter of a sample is found by a single cycle compressionof the sample between two circular stainless steel plungers of a tiparea of 2 mm² with a surface measuring 1 mm by 2 mm, for each. Thevelocity of compression is 1 mm/sec. When the pressure attains a levelof 1.0 grams force/cm² (gf/cm²) the top plunger retracts at the samevelocity of 1 mm/sec. The diameter is taken during the compression ofthe sample at the pressure of 0.5 gf/cm² as the plungers first movetoward each other. This test is first conducted on the first zone (i.e.,the one having a diameter corresponding to the generally cylindricalshape) at its visibly narrowest diameter on the sample by placing thatspot at the center of the test plunger (i.e., and the plungers having asufficient spacer attached to their surfaces to avoid compressing thesecond zone during this part of the measurement), and then operating thetest equipment to so measure. After the diameter of the first zone ismeasured, then the diameter of the second zone (i.e., the one having adiameter corresponding to generally non-cylindrical shape) at itsvisibly widest diameter on the sample, is measured for that same sampleby placing that spot at the center of the test plunger (i.e., and theplungers having the spacer removed so they have a completely smoothsurface), and then operating the test equipment to so measure. Thediameter of each zone is measured to the closest hundredth of amillimeter for each sample.

All publications, patents, and patent documents cited in thespecification are incorporated by reference herein, as thoughindividually incorporated by reference. In the case of anyinconsistencies, the present disclosure, including any definitionsherein, will prevail. While the invention has been described in detailwith respect to the specific aspects thereof, it will be appreciatedthat those skilled in the art, upon attaining an understanding of theforegoing, may readily conceive of alterations to, variations of, andequivalents to these aspects which fall within the spirit and scope ofthe present invention, which should be assessed accordingly to that ofthe appended claims.

What is claimed is:
 1. A dual mode absorbent tampon comprising: a massof absorbent material compressed into a generally cylindrical shape, ina first mode of the tampon; the mass of absorbent material comprising ahomogeneous mixture of a plurality of fibers which comprise at least afirst type of fiber and a second type of fiber, where the first type offiber is bondable to fibers of the plurality of fibers; and, at least aportion of the first type of fibers being bonded in a pre-determinedpattern to adjacent fibers of the plurality of fibers wherein absorptionof liquid by the plurality of fibers causes at least a portion of themass of absorbent material to expand into a non-cylindrical shape whichis dependent upon the pre-determined pattern, in a second mode of thetampon.
 2. The absorbent tampon of claim 1 wherein the second type offiber is not autogenously bondable to other second type fibers.
 3. Theabsorbent tampon of claim 1 wherein the second type of fiber is anatural type fiber.
 4. The absorbent tampon of claim 1 wherein the firsttype of fiber is autogenously bondable with fibers of the plurality offibers.
 5. The absorbent tampon of claim 1 wherein the first type offiber is thermally or radiation bonded to adjacent fibers of theplurality of fibers.
 6. The absorbent tampon of claim 1 wherein thenon-cylindrical shape comprises a member from the group consisting ofmushroom shaped, bottle shaped, and cone shaped.
 7. The absorbent tamponof claim 1 wherein the non-cylindrical shape comprises a first zone andan adjacent second zone, with the first zone having a first Diametercorresponding to the generally cylindrical shape and the second zonehaving a second Diameter corresponding to the non-cylindrical shape suchthat the second Diameter is greater than the first Diameter as measuredaccording to the Radial Expansion Test.
 8. The absorbent tampon of claim1 wherein the non-cylindrical shape comprises a first zone and anadjacent second zone, with the first zone having a first Diametercorresponding to the generally cylindrical shape and the second zonehaving a second Diameter corresponding to the non-cylindrical shape suchthat the second Diameter is at least 10% greater than the first Diameteras measured according to the Radial Expansion Test.
 9. The absorbenttampon of claim 8 wherein the second Diameter is at least 15% greaterthan the first Diameter.
 10. The absorbent tampon of claim 8 wherein thesecond Diameter is at least 20% greater than the first Diameter.
 11. Theabsorbent tampon of claim 1 wherein the second type of fiber is anatural type of fiber that does not autogenously bond to other secondtype fibers.
 12. The absorbent tampon of claim 1 wherein the mass ofabsorbent fibers are formed by airlaying the plurality of first andsecond type fibers.
 13. The absorbent tampon of claim 1 whereinautogenous bonds are located around the surface of the tampon andthereby help impart a smooth appearance to the tampon after removal frompackaging and prior to use of the tampon.
 14. The absorbent tampon ofclaim 1 wherein the tampon includes a string attached therewith and thestring is bonded with the mass of absorbent material.
 15. The absorbenttampon of claim 1 wherein the tampon includes a string attachedtherewith and the string is autogenous bonded with the mass of absorbentmaterial.
 16. The absorbent tampon of claim 1 wherein the tamponincludes a string attached therewith and the string comprises aplurality of string fibers including at least a first type of stringfiber being bondable to adjacent fibers and the string is autogenousbonded with the mass of absorbent material.